Impact switch



G. YUNKER IMPACT SWITCH Aug. 23, 1955 Filed March 16, 1953 EEQREE YL/NKER INVENTOR.

ATTY

United States Patent IlVIPACT SWITCH George Yunker, Portland, 0reg., assignor of thirty per cent to Edwin E. Meier and fifteen per cent to Byron H. Ginther, both of Portland, Oreg.

Application March 16, 1953, Serial No. 342,311

3 Claims. (Cl. ZOO-61.5)

This invention relates to improvements in automatic electrical switches of the type shown and described in my co-pending application Serial No. 307,345, filed August 30, 1952, and especially adapted for use with the electrical systems of engine-driven vehicles. As therein pointed out it is one of the principal objects of the invention to provide a switch of this character which will automatically open the electrical circuit within which it is embraced upon collision or upset of the vehicle.

It is one of the principal objects of the present invention to provide a switch of this character wherein the switch-actuating mechanism is in the form of a simple and effective responsive inertia unit comprising a normally vertically disposed shaft swingably mounted at its bottom end and weighted at its top end so that upon collision or upset of the vehicle or upon lateral impact from any direction, said shaft will tilt by the overbalance of its weighted end to instantly force the switch into an open or circuit-breaking position.

A further object is to provide said unit with adjustable tilt-resisting means which may be increased or diminished so as to require greater or less force to actuate said weighted shaft.

These and other objects will appear as my invention is more fully hereinafter described in the following specification, illustrated in the accompanying drawings and finally pointed out in the appended claims.

Referring to the drawing:

Figure l is a side elevation of the invention with parts in section and fragments broken away for convenience of illustration.

Figure 2 is a top plan view of Figure l with the cover removed and partly in section along the line 22 of Figure 1.

Figure 3 is an enlarged side view of the switch-actuating mechanism.

Figure 4 is a sectional end view taken along the line 44 of Figure 2.

Referring now more particularly to the drawing:

In Figure 1, reference numeral 1 indicates a fragment of a battery casing having the usual binding post or battery terminal 2 extending upwardly from its top surface and which may be either the plus or minus terminal since the invention is readily adaptable to either.

The invention comprises an elongated base 3 which may be made of micarta, hard rubber, fiber, Bakelite or any other suitable insulating material. The base is formed with a vertical opening 4 whose upper end opens into a recess 5 extending to the outside of the base. The underside of the base is undercut as at 6 to receive the base or supporting feet 7 of a battery terminal clamp generally indicated at 8 and which is secured to the base by means of screws 9. The clamp is in cylindrical form having a tapered inside diameter corresponding with the usual taper of the battery terminal. One wall of the cylinder 8 is split vertically as at 10 and formed with ears 11 provided with a clamping bolt 12, so that as the bolt is advanced on its threads cylinder 8 will be- 2,716,166 Patented Aug. 23, 1955 come securely locked to the battery terminal. The opposite wall of the cylinder is extended upwardly and then horizontally as at 13 to provide an electrical contact. A companion electrical contact 14 is provided by the horizontal portion 14 of a vertical post 15 formed integral with a supporting arm 16 embedded within and secured to the base 3 by means of screws 17 extending upwardly from the bottom of the base. The arm 16 extends outwardly from the base as shown in Figure 2 and terminates in an upwardly tapering projection 18 to provide a binding post for a cable clamp 19, secured to the terminal end of a battery cable 20 which may extend to a ground connection or to the opposite side of the electrical system of the vehicle to which the invention is applied.

The base is provided with a cover in the form of a housing 21 which may be of any desired fanciful or ornamental design and secured to the base 3 by means of screws 22 extending upwardly through apertures 23 formed in the base. The cover 21 is cast integral with a vertically extending cylindrical housing 24 whose top wall is formed with a concentric opening 25. The bottom of the housing 24 is internally threaded to adjustably receive an externally threaded closure disc 25A having a concentric vertical sleeve 26 secured to, or cast integral with it. The sleeve forms a hearing within which is slidably mounted for vertical movement a shaft 27 whose top end is provided with or enlarged into a disc 28 slidably supported by the inside walls of the housing 24. The opposite or bottom end of the shaft 27 is reduced in diameter as at 29 (see Fig. 3) for secure attachment by a forced fit to a cap 30 flanged as at 31 at its upper end and circumferentially grooved as at 32 near its opposite end. A bushing 33 made of insulating material is flanged outwardly as at 34 at its top end and secured to the exterior of the cap 30 and to the underside of the flange 31 of the cap. A metallic disc 35 is secured to and insulated from the cap 30 by means of the insulating bushing 33.

As shown in full lines in Figures 1 and 3, the disc 35 is in contact with the contacts 13-14 and the electrical circuit is thereby closed between the battery terminal 2 and the terminal end 19 of the battery cable 20. The bottom end of the cap 30 is slidably mounted in a vertical opening 36 in the base 1 which cooperates as a bearing with those provided by the sleeve 26 and the interior of the housing 24 for the shaft 27 and its related parts. The lower portion of the shaft 27 is surrounded by a coil spring 35A whose upper end bears against the underside of the disc 35 and whose opposite end bears against the top surface of the base 3 to normally maintain the shaft 27, disc 28 and disc 35 in their elevated circuit-closed position, as aforesaid.

Disposed within the housing 24 and resting upon the disc 28 is a pressure disc 37 secured to or formed integral with a normally vertically reposing actuating lever 38 which is enlarged as at 39 into a ball segment. The ball segment operates within the opening 25 in the top wall of the housing and effectively seals the same throughout the entire operative range of the lever, against ingress of dirt or other foreign substances and also against escapement of lubricant retained within the housing.

Adjustably secured to the lever 38 by means of a set screw 40 is a Weight 41 whose inertia will cause the lever to tilt, for example, into the broken line position shown in Fig. 3, or in a direction opposite to that of any impact or collision. This tilting of the lever 38 will, of course, correspondingly tip or rock the pressure disc 37 formed on its bottom end. The tilting of the disc 37 in any direction will apply downward pressure to the plunger 27 through the medium of its disc 28 and this downward movement of the plunger will, of course, force the contact disc 35, secured to it, downwardly from and out of electrical contact with the contacts 13-14 to thereby open or break the circuit by the battery terminal 2 and the battery cable terminal 19.

A compression spring 42 is disposed within the housing 24 and bears upwardly against the disc 28 and against the adjustable closure disc 25A which, when rotated, will increase or diminish the upward pressure against the disc 28 so as to require greater or less force to actuate or tilt the lever 38 upon collision or upset of the vehicle but which will not yield to ordinary road shock during normal operation of the vehicle.

When the circuit is broken by downward movement of the contact disc 35, as aforesaid, the shaft 27 is automatically locked in its lowered position by means of a locking lever 43 pivotally attached as at 44 to the base and formed at its inner end with a hook portion 44A adapted to engage with the groove 32 in the cap 30 under the influence of a compression spring 45 embedded within the base 3 and having one of its ends bearing against the lever 43 near its outer end. The lever terminates in a finger grip 47 exterior of the base for convenience in disengaging the hook portion 44- from the groove 32 to allow the shaft to be forced upwardly again by the compression springs 37 and 42 into a circuit-closed position.

In attaching the device in its entirety completely assembled as shown in Fig. 1 to any storage battery, the clamping bolt 12, accessible through the recess 5, is retracted on its threads to expand the battery terminal clamp 8 so that it will fully embrace the battery terminal 2 and allow the base 3 to rest squarely upon the top surface of the battery. Following this the bolt 12 is advanced on its threads to securely clamp the device to the battery terminal through the medium of the battery clamp.

While I have shown particular forms of embodiment of my invention, 1 am aware that many minor changes therein will readily suggest themselves to others skilled in the art without departing from the spirit and scope of the invention. Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. An impact switch of the character described comprising in combination, a base, a clamp secured to the base and extending upwardly therethrough for attaching the base to a terminal of a battery, a contact carried by the clamp and elevated from the base, a companion elevated contact carried by the base and insulated therefrom, a plunger slidably mounted beneath said contacts for vertical movement with respect to the base, a contact plate carried by the plunger and adapted to make and break an electrical circuit across the underside of said contacts, a normally vertically reposing lever resting upon said plunger, a weight adjustably attached to said lever and adapted to overbalance and tilt said lever in a direction opposite to that of any impact or collision to depress the plunger and said contact plate out of contact with said contacts, and adjustable resilient means surrounding said plunger for normally maintaining the same in an elevated position and said contact plate in circuit-closing position across said contacts.

2. An impact switch of the class described comprising in combination a base, a battery terminal clamp extending upwardly through the base and adapted for attachment to a battery terminal, an extension formed on said clamp to form an electrical contact elevated from the base, a companion contact extending upwardly from the base and also outwardly therefrom and terminating at its outer end in an auxiliary terminal adapted for attachment to an electrical cable, a cover removably secured to the base, a vertical bearing extending upwardly from the cover, a vertical shaft disposed between said contacts and slidably mounted within said vertical bearing at its upper end and at its opposite end within a vertical opening formed in said base, a contact plate secured to said shaft beneath said contacts, resilient means surrounding said shaft for normally maintaining contact between said plate and said contacts, a weighted lever resting upon the top end of said shaft and extending upwardly from said vertical bearing whereby tilting of said lever in any direction by an impact will force said shaft downwardly and the contact plate carried thereby out of contact with said contacts to break the electrical circuit between said main and auxiliary battery terminals, and releasable locking means for maintaining said shaft and contact plate out of contact with said contacts.

3. An impact switch of the class described comprising in combination, a base made of insulating material and having a vertical opening formed therethrough, a battery terminal clamp extending through said opening and secured to said base and adapted to secure the base to a battery terminal, the top end of the clamp having an upwardly and outwardly extending electrical contact, a companion electrical contact secured to the base and elevated therefrom, an auxiliary terminal formed integral with said companion contact, said base having a vertical opening formed therein, a vertical shaft slidably mounted for vertical movement within said opening, a contact plate carried by said shaft and insulated therefrom, resilient means disposed below said plate for normally maintaining it in contact with the underside of said contacts in a circuit-closed position, a vertical housing carried by the base, said shaft terminating at its upper end in a disc slidably mounted within said housing, a lever extending upwardly through the top of said housing, a weight adjustably attached to said lever, the bottom end of the lever terminating in a pressure disc resting upon said first-mentioned disc and adapted when tilted to depress said disc, shaft and contact plate downwardly to move said plate away from said contacts into circuitopen position, and spring-urged horizontally swingable releasable locking means carried by the base and adapted to engage said shaft when in a downward position to hold said contact plate in a circuit-open position.

References Cited in the file of this patent UNITED STATES PATENTS 2,027,709 Slebos Ian. 14, 1936 

